| Study |
Bias |
| Randomisation process |
Deviations from intended interventions |
Missing outcome data |
Measurement of the outcome |
Selection of the reported results |
Overall |
| Authors' judgement |
Support for judgement |
Authors' judgement |
Support for judgement |
Authors' judgement |
Support for judgement |
Authors' judgement |
Support for judgement |
Authors' judgement |
Support for judgement |
Authors' judgement |
Support for judgement |
| Espin‐Basany 2005 |
Some concerns |
There was no information on method of randomisation, there was no baseline imbalance that would suggest a problem with randomisation. |
Low risk of bias |
Both participants and those delivering the intervention were aware of intervention received. There were no deviations from intervention. |
Low risk of bias |
>95% of randomised patients were analysed. |
Low risk of bias |
The assessors were not blinded, but it is unlikely that knowledge of the intervention would have influenced the assessment, as the occurrence of postoperative ileus is associated with clear clinical diagnostic criteria. |
Some concerns |
No pre‐registered method (registry or protocol) available. |
Some concerns |
Some concerns about the lack of information about the randomisation method and about a predefined analysis plan. |
| Hata 2016 |
Low risk of bias |
The generation of the randomisation sequence and the allocation concealment were appropriate. There was no baseline imbalance that would indicate a problem with randomisation. |
Low risk of bias |
Both participants and those delivering the intervention were aware of intervention received. There were no deviations from intervention |
Low risk of bias |
>95% of randomised patients were analysed. |
Low risk of bias |
The assessors were not blinded, but it is unlikely that knowledge of the intervention would have influenced the assessment, as the occurrence of postoperative ileus is associated with clear clinical diagnostic criteria. |
Low risk of bias |
This trial was registered with ClinicalTrials.gov, Number NCT00508690. |
Low risk of bias |
Low risk of bias in all domains. |
| Ikeda 2016 |
Low risk of bias |
The generation of the randomisation sequence and the allocation concealment were appropriate. There was no baseline imbalance that would indicate a problem with randomisation. |
Low risk of bias |
Both participants and those delivering the intervention were aware of intervention received. There were no deviations from intervention. |
Low risk of bias |
>95% of randomised patients were analysed.
For our meta‐analysis, however, only patients who had MBP and oAB as intervention were eligible. The relevant data was provided to us by the study authors. |
Low risk of bias |
The infection control doctors and nurses who determined SSIs were blinded to the assignment. The ward doctors and nurses who probably diagnosed all other outcomes were not blinded, but it is unlikely that knowledge of the intervention would have influenced the assessment, as the occurrence of postoperative ileus is associated with clear clinical diagnostic criteria. |
Low risk of bias |
This trial was registered with the UMIN Clinical Trials Registry (UMIN000019339). |
Low risk of bias |
Low risk of bias in all domains. |
| Rybakov 2021 |
Low risk of bias |
The generation of the randomisation sequence and the allocation concealment were appropriate. There was no baseline imbalance that would indicate a problem with randomisation. |
Low risk of bias |
Both participants and those delivering the intervention were aware of intervention received. There were no deviations from intervention. |
Low risk of bias |
77 % of the 150 randomised patients were analysed. 34 participants were excluded due to unexpected changes in surgical procedure (e.g. inoperability or no restoration of bowel continuity via anastomosis; 18 in the oral + IV AP group and 16 in the IV AP group). None of the patients were lost to follow‐up. |
Low risk of bias |
The assessors were blinded to the allocation of patients. |
Low risk of bias |
The study protocol was registered on ClinicalTrials.gov (registrationnumber NCT03436719). |
Low risk of bias |
Low risk of bias in all domains. |
| Papp 2021 |
Low risk of bias |
The generation of the randomisation sequence and the allocation concealment were appropriate. There was no baseline imbalance that would indicate a problem with randomisation. |
Low risk of bias |
Both participants and those delivering the intervention were aware of intervention received. There were no deviations from intervention. |
Low risk of bias |
89 % of the 597 randomised patients were analysed.
The reasons for exclusion were mostly protocol violations (n=71) or that no anastomosis was created during surgery (n= 47). 7 patients were excluded due to adverse events. |
Low risk of bias |
The assessors were blinded to the allocation of patients. |
Low risk of bias |
This trial was registered as EudraCT 2015‐005614‐27 |
Low risk of bias |
Low risk of bias in all domains. |
| Arezzo 2021 |
Low risk of bias |
The generation of the randomisation sequence and the allocation concealment were appropriate. There was no baseline imbalance that would indicate a problem with randomisation. |
Low risk of bias |
Both participants and those delivering the intervention were aware of intervention received. There were no deviations from intervention. |
Low risk of bias |
All participants were included in the analysis
For our meta‐analysis, however, only patients who had MBP and oAB as intervention were eligible. The relevant data was provided to us by the study authors. |
Low risk of bias |
The assessors were not blinded, but it is unlikely that knowledge of the intervention would have influenced the assessment, as the occurrence of postoperative ileus is associated with clear clinical diagnostic criteria. |
Low risk of bias |
The trial was registered with ClinicalTrials.gov (NCT: 04438655). |
Low risk of bias |
Low risk of bias in all domains. |
